The Bears have tabbed Mel Tucker to become the team's defensive coordinator, according to three league sources.
The Bears are expected to formally announce the hire Friday evening.
Tucker had been the Jacksonville Jaguars defensive coordinator since 2009. Although the Jaguars unit was terrible last season, the defense was ranked 6th overall in 2011. Tucker has extensive college and pro coaching experience.
Tucker has run both 4-3 and 3-4 defenses, and he's worked with the likes of Jack Del Rio and Nick Saban.
He served as the Jags interim head coach after Del Rio was fired, and he's interviewed for a handful of head coaching vacancies.
Former Bears and Jaguars safety Chris Harris called him an "outstanding coach."
Asked why, Harris said, "He's a guy that understands how teams are trying to attack him.
"He believes in his system and doesn't panic when things aren't going to plan."
The hire is a significant one since Tucker will essentially run the defense because new head coach Marc Trestman has an extensive offensive background.